1. Field of the Invention
This invention relates generally to a robbery signal device, and particularly to a sign displayable outside a place of business for warning of a robbery taking place within the place of business.
2. Description of the Prior Art
The risk to merchants, banks, and the like, from armed robbery and similar crimes is a serious problem in our morally decaying and economically troubled society. The situation has reached a point where many businesses today experience such high instances of robberies that police-stakeouts are maintained in the vicinity of such businesses. To compound the problem, persons in the vicinity of a robbery, or passing by the scene of the crime in a motor vehicle or other conveyance, are unaware that a crime is being committed and, accordingly, fail to note descriptions and license plate numbers of get-away cars, description of persons leaving the scene of the crime, and other information useful to law enforcement officers in either stopping the crime while it is in progress or eventually apprehending the perpetrator or perpetrators of the crime.
As can be appreciated, if a merchant, banker, or other business or professional person being robbed could alert persons in the vicinity of the crime, the police would stand a better chance of having outside witnesses to said crime resulting in more arrests and convictions of robberies. Outside witnesses would be able, without risk to themselves, to get car descriptions and possibly license numbers of get-away vehciles used by the robbers. Further, the witnesses would be able to give better descriptions of the thieves inasmuch as the witnesses were forewarned of the robbery taking place and would be in a position to get a good look at the robbers without endangering their own lives. Most importantly, outside witnesses would be able to notify police or the local authorities of a robbery taken place, resulting in quicker action being taken to apprehend the criminals and hopefully to interrupt the robbery, or similar crime, while same is still in progress.
Another significant advantage of a device which warns the public that a robbery is taking place in a place of business is that such warning will prevent the public from walking into the place of business and being involved in the robbery.
Accordingly, it has been proposed to provide various visual warnings of a robbery, and the like, being committed within a building, or part of a building, outside of which a warning sign, actuable from within the building is displayed. Examples of such devices previously proposed may be found in U.S. Pat. Nos. 1,267,911, issued May 28, 1918 to M. Schoulder; 1,964,353, issued June 26, 1934 to S. J. Hodos; 2,518,979, issued Aug. 15, 1950 to J. R. Davidson; 2,770,690, issued Nov. 13, 1956 to T. J. Sanders; and 2,803,810, issued Aug. 20, 1957 to E. M. Evans et al. A major disadvantages of these known warning devices, however, which has prevented the devices form becoming popular and in general use, is that they fail to alert persons except those in the immediate vicinity of the place of business being robbed. In this day of the automobile when a great many banks. fast-food businesses, and the like, are located along highways where the only passerbys are in motor vehicles and similar conveyances, it is necessary that the warning be visible to persons passing by the place in a vehicle. Further, when police stake-outs are resorted to, it is necessary that such a warning sign be seen at a substantial distance from the place of business, say one-fourth to one-half mile, so the law enforcement officer can be watching a place of business, and preferably several places of business, from a substantial distance without being conspicuous to perpetrator or perpetrators of the crime.
In addition, these known devices usually are conspicuous when not in actual use. U.S. Pat. No. 3,913,092, issued Oct. 14, 1975 to G. R. Klingenberg, discloses an example of an illuminated sign formed by indicia disposed on a transparent face of a sign so that the indicia is visible at all times. Further, U.S. Pat. Nos. 3,089,060, issued May 7, 1963 to Horino, and 3,694,062, issued Sept. 26, 1972 to Koenig, are pertinent as disclosing examples of a blinking signalling device and a stroboscopic display, respectively.
U.S. Pat. No. 2,998,667, issued Sept. 5, 1961 to J. W. Darnel, et al, discloses a message conveying apparatus employing fluorescent tubes in a normally blacked-out display, while U.S. Pat. No. 3,780,284, issued Dec. 18, 1973 to F. A. Dewhirst sets forth a lamp enclosure in which a neon lamp is employed to illuminate a message provided on a translucent lens. In addition, U.S. Pat. No. 1,946,781, issued Feb. 13, 1934 to W. H. Davidson, discloses an example of a control system for use with alarm systems for banks and the like.